Bottom to shell weld

[Opslagtank]

In de BS2654 leg length of the bottom/shell filletweld should be at least equal to the shell thickness. In the EN 14015 it is the throath thickness that should be minimum equal to the shell thickness. What is the minimum leg length or throat thickness for the fillet weld of a 8 mm shell to an 8 mm annularplate in API 650?

Please advise

 

[Bonswa]

In your case it's going to be 8mm fillet weld.

5.1.5.7 Shell-to-Bottom Fillet Welds
a. For bottom and annular plates with a nominal thickness 13 mm (1/2 in.), and less, the attachment between the bottom edge of the lowest course shell plate and the bottom plate shall be a continuous fillet weld laid on each side of the shell plate. The size of each weld shall not be more than 13 mm (1/2 in.) and shall not be less than the nominal thickness of the thinner of the two plates
joined (that is, the shell plate or the bottom plate immediately under the shell) or less than the following values:

Nominal Thickness of Shell Plate Minimum Size of Fillet Weld
(mm) (in.) (mm) (in.)
5 0.1875 5 3/16
>5 to 20 >0.1875 to 0.75 6 1/4
>20 to 32 >0.75 to 1.25 8 5/16
>32 to 45 >1.25 to 1.75 10 3/8

 

[Opslagtank]

Bonswa, If fillet size the leg length or the throat thickness?

 

[Bonswa]

That's the leg length. Open API-650 to section 5 and look at Figure 5-3C. Its a design of a shell-to-bottom weld for greater that 13mm, however it still shows details.

 

[Opslagtank]

Thanks Bonswa, I've posted this thread because I only have the BS and the EN to review.
Regards

 

Opslagtank,

Just a remark regarding BS and EN bottom-to-shell weld size:
In BS2654, as well as in EN14015, the fillet weld size shall be equal to the thickness of the bottom plate (annular or sketch) when shell thickness > bottom thickness.
For BS, it means that the leg length shall be at least the size of the thinnest plate (bottom).
For EN, it means that the weld throat shall be at least the size of the thinnest plate (bottom).

When shell thickness < bottom thickness, you have to check the tables.